In order to meet the demand for wireless data traffic soring since the 4th generation (4G) communication system came to the market, there are ongoing efforts to develop enhanced 5th generation (5G) communication systems or pre-5G communication systems. For the reasons, the 5G communication system or pre-5G communication system is called the beyond 4G network communication system or post LTE system.
For higher data transmit rates, 5G communication systems are considered to be implemented on ultra-high frequency bands (mmWave), such as, e.g., 60 GHz. To mitigate pathloss on the ultra-high frequency band and increase the reach of radio waves, the following techniques are taken into account for the 5G communication system: beamforming, massive multi-input multi-output (MIMO), full dimensional MIMO (FD-MIMO), array antenna, analog beamforming, and large scale antenna.
Also being developed are various technologies for the 5G communication system to have an enhanced network, such as evolved or advanced small cell, cloud radio access network (cloud RAN), ultra-dense network, device-to-device (D2D) communication, wireless backhaul, moving network, cooperative communication, coordinated multi-point (CoMP), and interference cancellation.
There are also other various schemes under development for the 5G system including, e.g., hybrid FSK and QAM modulation (FQAM) and sliding window superposition coding (SWSC), which are advanced coding modulation (ACM) schemes, and filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA) and sparse code multiple access (SCMA), which are advanced access schemes.
Recently under research is such technology as machine-type communication (MTC) equipping all things and sensors with communication functionality so that they can intelligently gather and mutually transfer information. Machine-to-machine (M2M) communication or Internet-of-things (IoT) is also termed in the same meaning as MTC.
As communication techniques to implement MTC, short-range communication schemes and remote communication schemes may come into use. Short-range communication schemes for MTC include small coverage communication schemes, such as Bluetooth (or Bluetooth Low Energy (BLE)), near-field communication (NFC), or Wireless-Fidelity (Wi-Fi). The remote communication technology for MTC encompasses broad-coverage CIoT techniques. As CIoT technology for configuring cells to embody the IoT, there are standardized techniques, such as 3rd generation partnership project (3GPP) GSM EDGE radio access network (GERAN) CIoT, 3GPP long term evolution (LTE) Enhanced-MTC, 3GPP LTE narrow band IoT (NB-IoT) and non-standardized techniques, such as SIGFOX, On-Ramp, or Weightless. The 3GPP New RAT (NR) study item presently under discussion for standardization are also in progress for standardization of massive-MTC (mMTC) scenarios, as a CIoT technology, and 3GPP Rel-14 is scheduled to proceed with enhanced narrowband-IoT (eNB-IoT).
Although different from application to application, information exchanged between devices on the cellular-based MTC is generally small in size (i.e., the inter-MTC device data rate is low) and is relatively infrequently subject to communication (i.e., a low duty cycle), and is relatively less sensitive to latency.
Further, a major CIoT, i.e., metering (e.g., water supply metering, rainfall metering, or gas metering) mostly involves periodic uplink (UL) communication. For reference, the working assumption of the GERAN CIoT study item assumes that 80% of UE UL traffic are for periodic reporting.
MTC devices performing periodic communication may predict the period of data UL transmission. Accordingly, such a process may be redundant and unnecessary that periodically communicative MTC devices perform random access (RA) and receive UL grants at each UL transmission.